krita_sample_color

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false. The description adds meaningful behavioral context: it is a non-mutating read, it samples a 'settled' projection pixel, and it explicitly guarantees the foreground color is unchanged. This goes beyond the annotations and clarifies side-effect behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single well-structured sentence that front-loads the core action and includes only high-value details: the color format, the optional source, the output, and the side-effect guarantee. There is no filler or redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The description covers the main operation and return value, and annotations cover safety. However, it omits important invocation details such as coordinate system/origin for x/y, what 'settled' means, and how the optional node_id interacts with the canvas. With five parameters and no output schema, a bit more context would be needed for fully reliable use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate for undocumented parameters. It only hints that node_id selects an explicit node and that x/y locate a pixel; it does not explain coordinate origin, units, projection details, or the roles of instance_id/document_id. The parameter names are somewhat self-explanatory, but the description adds minimal semantic value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific action ('read'), a precise resource ('one settled RGBA/U8/sRGB projection pixel'), and the optional source ('canvas or explicit node'). It also names the output ('hex color and alpha'), making the tool's purpose unambiguous even among many siblings.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies when to use the tool: when a single pixel color is needed without changing the foreground color. However, it does not explicitly contrast with alternatives such as previews, inspection tools, or other read operations, so an agent must infer the appropriate use case.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.